This story is a sidebar to the March 2023 cover story.

A marijuana grow house succeeds by imitating Mother Nature—something it can’t do without electricity. Electric power allows a grow house to replace sunlight with grow lights and run fans, air conditioners, heaters and dehumidifiers to keep conditions just right for the cannabis plants to flourish.

“We’re trying to not exactly mimic the outdoors but optimize it—tweak it a little bit and get better results,” says Mark Walker, one of the owners of Pharma Flower in Oklahoma. “We are trying indoors to create the perfect climate and then to maintain that consistently.”


The small company grows cannabis for medical use from a nondescript, 6,000-square-foot building on Main Street in the tiny town of Fairfax, which has a population of less than 1,500 people. Oklahoma voters legalized marijuana for medical use in 2018.

The Pharma Flower grow house, which is served by Cleveland-based Indian Electric Cooperative, is divided into four main rooms for each stage of the plants’ growth and harvest. It uses about 70 LED lights of 650 watts each, Walker says.

After about three weeks, the clones have grown to about 8 inches tall and are ready to be planted in soil, Walker says.

“This vegetative period lasts between three and five weeks, and our lights are on 18 hours a day,” he explains. “After about four weeks, the plants grow from about 8 or 10 inches tall to about 4 feet tall.”

The grow lights are then cut back to 12 hours a day to mimic autumn, when the plants flower and produce the cannabis buds that patients consume. The plants are kept in the flowering stage for about eight to 10 weeks and will grow another 10% to 20% before they’re harvested, Walker says.

At harvest time, the stems are cut, and the plants are hung in a room to dry and cure for about three weeks. They are then trimmed down to flowers and made ready for sale to medical dispensaries.

“For us, reliable electricity is critical,” Walker says. “If our plants are in the vegetative stage and we lose power, we’re, in effect, triggering those plants to think it’s fall, and they will begin to convert into the flowering stage before we want them to. That’s very bad for us.”

Without continuous, dependable electric power, “an indoor grower simply cannot exist,” he says.

“We were extremely grateful that Indian Electric Cooperative has never had to have a rolling blackout, thanks to their good planning,” Walker says. “Two years ago, during bad winter storms, other providers had to have rolling blackouts. … Since 2020, we haven’t had a power outage longer than five minutes. IEC has been extremely reliable.”

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